Furuno 1942 MARK-2 manual Selecting Pulsewidth, Guard Alarm, Selection of guard zone type

3.Select “6. Int Reject.”

4.Select level desired by operating the omnipad.

5.Press the [ACQ/ENTER] key.

6.Press the [MENU] key to close the menu.

IR1, IR2 or IR3 appears at the bottom right corner on the display when the interference rejection circuit is turned on.

3.6 Selecting Pulsewidth

Pulsewidth is the time in microseconds nec- essary to transmit a single radar pulse. The longer the pulsewidth the greater the direc- tion range capability, however range accu- racy and range resolution are reduced.

Pulsewidth can be selected to short or long on the 1.5 and 3 nautical mile ranges.

1.Press the [MENU] key.

2.Select “OTHER MENU” and press the [ACQ/ENTER] key.

3.Select “7. Pulselength.”

4.Select Short or Long by pressing the omnipad.

5.Press the [ACQ/ENTER] key to select.

6.Press the [MENU] key to close the menu.

3.7 Guard Alarm

The guard alarm allows the operator to set the desired range and bearing for a guard zone. When ships, islands, landmasses, etc. violate the guard zone an audible alarm sounds and the offending target blinks to call the operator’s attention.

CAUTION

The guard alarm is a useful anti-collision aid, but does not relieve the operator of the responsibility to also keep a visual lookout for possible collision situations. The alarm should never be used as the sole means for detecting possible collision situations.

Selection of guard zone type

The guard alarm can be set to sound when a target either enters or exits the guard zone. You can select which type of guard alarm you want through the menu.

In alarm

The alarm sounds on targets entering the guard zone. “G (IN)” appears at the top right- hand corner when the In alarm is selected.

Out alarm

The alarm sounds on targets exiting the guard zone. “G (OUT)” appears at the top right-hand corner when the Out alarm is selected.

	Dashed line:
	no alarm
	Guard
IN ALARM	zone
	OUT ALARM

Figure 3-7 In and Out alarms

Selecting guard zone type

1.Press the [MENU] key, select “OTHERS MENU,” and then press the [ACQ/EN- TER] key.

2.Select “17. Guard Mode” and “In” (alarm on target entering zone) or “Out” (alarm on target exiting zone) by operating the omnipad.

3.Press the [ACQ/ENTER] key.

4.Press the [MENU] key to close the menu.

Setting a guard zone

1.Mentally create the guard zone you want to set. Figure 3-8 shows an example.

2.Operate the omnipad to set the cursor on point A (or B). Press the [GUARD] key. “*G (IN)” or “*G (OUT),” with asterisk blink- ing, appears at the top right-hand corner of the display. See Figure 3-8 (2). (The asterisk indicates the guard zone is par- tially set.)

3-4